Electric-switch-contact holder.



D. L. LINDQUIST & D. LARSON. ELECTRIC SWITCH GONTAOT 110mm. APPLIOATiON FILED MAY 7, 1908.

1916,8373 Patented Feb. 6, 1912 UNITED STATES PATENT OFFICE.

DAVID L. LINDQUIST AND DAVID LARSON, 0F YONKERS NEW YORK, ASSTGNORS TO OTIS ELEVATOR COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

ELEGTRIC-SWITCH-CONTAOT HOLDER.

Specification of Letters Patent.

Patented Feb. 6, 1912.

Application filed May 7,1908. Serial No. 431,523.

To all whom it may concern:

Be it known that we, DAVID L. LIN'o UIsr and DAVID LARSON, subjects of the King of Sweden, residing at Yonkers, in the county of Westchester and State of New York, have invented a new and useful Improvementin Electric-Switch-Gontact Holders, of which the following is a specificatiom Cur invention relates to an electric switch contact holder in which abushing or sleeve of insulating material is used to separate the switch contact from the switch arm or support which carries the contact, and'one of the objects-of the invention .is to provide a construction in which the parts are securely held in position in such a manner that the operation will be un'aifected by the unequal expansion and contraction of the insulating material and metal;

The accompanying drawing is a side elevation view, partly in section, of an electro magneticswitch showing the application-of our invention.

As here shown, to a base or support 1- of slate or other insulating material is secured a. bracket 2, to which is pivoted at 3 the switch arm 4. The outward movement of the arm 4 is limited by a stop 5 in the path of movement of an extension 6 of the switch arm. An electro-magnet comprising a laminated frame 7 and a winding 8 is secured to the base 1, and its armature 9 is secured to the switch arm 4. The magnet when energized operates to close the switch, and a coil spring 10 opens the switch when the magnet is deenergized.

The switch arm 4 carriesa movable contact 12 in the form of a-fiat plate or disk having a stem 13, preferably rectangular or non-circular in cross-section, extending through the switch arm. The movable contact is insulated from the switch arm by abushing of insulating material comprising a sleeve 14 closely fitting the stem 13 and formed with an integral flange 15 which bears against the contact 12. An insulating washer or plate 16 which is preferably made somewhat thicker than the flange 15, fits snugly on the stem 13, and is recessed to receive the end of the sleeve 14. The stem 13 is pr vided with an integral extension in the form of a screw-threaded rod 18. A metal disk or plate 19 is mounted on this ed and bears against the shoulder formed at the end of .the stem 13. The rod 18 .forms a binding post for the: terminal 20 of a conductor 21 leading to the switch, said terminal bearing against the plate 19 and being clamped in position by the nuts 22 and23. A metal sleeve 24 is mounted on the insulating sleeve 14 and is provided at its front end with a flange 25 bearing againstthe flange. 15, the rear end of the metal sleeve abutting against the washer 16. The sleeve 24 extends loosely through an opening in the switch arm and is yieldingly held in its forward position by' a coil p i As, the switch arm is moved forward toward its closed position, the contact :12 engages the stationary contact 30 before the sw tch arm has reached itsforward limit of movement, and the continued movement of i the switch arm compresses the spring 27 and holds the switch contacts together with a yielding pressure. The spring 27 serves to hold the fiat surfaces of the contacts squarely in engagement, as there is sufiicient clearance between the sleeve 24 and the switch arm to permit angular movement of the. contact 12 in any direction which may be necessary to make the contact surfaces parallel. The insulation 14, 15 prevents the spring 27 from becoming overheated, and the sleeve 24'takes up wear.

' With the construction herein shown, the plate 19 prevents any material displacement of the insulating material, even when the parts are subjected to considerable variations in temperature and the consequent unequal expansion and contraction of the insulating and metal parts.

Any suitable form of stationary contact and holder may be used. As herein shown,

construction disclosed, as various changes in details of construction andarrengement of parts might be made by those skilled in the art withoutdeparting from the 'spirit and scope of the. invention.

The invention 18 applicable to various forms of switches, whether manually or an} tomatically operated, although the means "for yieldingly connecting the contact to the.

switch arm is especially adapted for absorbing the vibrations and securing a ood electrical connection of the contacts W ere an alternating current, 'electrosmagnet. is used tooperate the switch.

What we claim as new and desire to secure i by Letters Patent. of the United States is i g and contact plate.

form a stop to limitthe movement of said stem, and aplate mounted on the stem and 4 securing said sleeve or bushing against displacement. 2. In an electric switch, the combination with a contact plate, of a stem' extending therefrom, a reduced extension formed on the stem, a plate mounted onsaid extension, means for securing said plate againstthe end of the stem, an insulating flanged sleeve.

or bushing mounted on the stem, and a support having an opening in which the stem and the insulating sleeve are loosely mounted. p r

' 3. In an-electric switch, the combination with a switch arm having an opening there through, of a switch contact plate, .a-stem formed thereon and extending through said opening, an extension of reduceddiameter on said stem, a .plate mounted on said ex-- tension, a clamping nut securing said plate against the shoulderedend 'ofthe stem, a sleeve of insulating material 1 mounted on the-stem and having a flangerjat one end bearing against said contact plate, a disk or, washer of insulating"material forming a flange forthe opposite end of the sleeve and locatedbetween the switch armand .said

plate,- and a coils ring surrounding -said sleeve 'and located etween the, switch arm 4. In an electric switch,'the'combinationwith a contact plate, of a stem formed thereon, a sleeve of insulating material mounted on the stem and having an integral flange at one end bearing against the contact plate, a plate of insulating material mounted on the stem and forming a flange for the other end of said sleeve, a metalsleeve mounted on the insulatingsleeve and forming a stop for said plate of insulating material, and a plate secured to the stem and securing the insulating material against displacement.

'5. In'an electric switch, the combination with av support, of a contact, connections between the support andcontact permitting universal movement of the contact, and insulating material carried by, the contact and insulating it'from its support.

6. The combination with a supporting member having an opening extending therethrough, of a contact member extending through the opening, an insulating bushing on the contact member, and a metal sleeve on the bushing and extending loosely through said opening.

7. The combination with a supporting member having an opening therethrough, of

a switch contact movable in said opening, insulating material carried by said contact and insulating it from the supporting member, and means for yieldingly holding the contact at its limit of-movement relative to the supporting member. I 8. In a switch, he. combination with a support having an opening therethrough, of a contact formed with a stem extending through said opening, a bushing of insulating material on said stem, and a coil spring interposed between said support and the end of the bushing. 9. In a .switch, the combination with a switch arm having an opening therethrough, of a contact having a stem extending through said opening, a flanged sleeve of insulating material secured to the stem, and a'coilspring surrounding the sleeve and lo- :cated between the switch arm and the flange on the sleeve. V

10. In a switch, the combination with' a switch arm having an opening therethrough, of -a contact having a stem extending through the opening, a flanged sleeve of insulating material-surroundmg said stem, a flanged. metal sleeve mounte on the msulation and extending loosely through sa d opening, and a coil ring surrounding said sleeves. and yieldin y holding the contact in position: v

In testimony whereof, .we have signedour names to this 'ecification in' the presence of two subscribm witnesses.

,. DKVIDL. LINDQUIST.

DAVID LARSON. Witnesses: Oma. M.N1ssm-r,

JAims Copies of this patent may be obtained or five cents each, by addressing. the commissioner of Patents.

Washington, D. 0. 

